Centrifugal pump



.0. HAENTJENS CENTRIFUGAL PUMP.

APPLICATION FILED APRJ24. I919.

Patentd Aug. 12, 1919.

Z SHEETS-SHEET I.

INVENTOR YATTORNEY$ '0. HAENTJ ENS CENTIRIFUGAL PUMP,

APPLICATION FILED .APR- 24. 1919. 1,312,97 9. PatentedAug. 12,1919.

' YINQVENYTOR HQ I MBY Q7 UNITED STATES PATENT OFFICE. j

OTTO HAENTJENS, HAZLETON, PENNSYLVANIA.

CENTRiFUGAL PUMP.

To all whom it may concern:

.Be it known that I, OTTO HAENTJENS, a citizen of the German Republic, residing at Hazleton, in the county of Luzerne and State of Pennsylvania, and having a post- -office address care of Barrett, Haentjens &

Co. Hazleton, Pennsylvania, have invented certain new and useful Improvements in Centrifugal Pumps, of which the following is a specification. p Y

My invention relates to centrifugal pumps, and particularly to multi-stage pumps, the object of my invention being'toprovide a relatively low speed pump of eflicient, sim

-plified and improved construction. Among the features of improvement to which I may direct especial attention are, first, the arrangement of thepressure chamber in the foot-ofthe pump casing, thus lessening the height and weight of thestructure; second,

i the consequent lowered position of the axis of the driving shaft, which renders the'struc ture compact and also reduces the weight; third, the novel shape of the passage connecting the pump stages and through which the water passes with a sharp change of direction but without material frictional losses. Other features of improvement will also appear in the accompanying drawings in which I Figure 1 is a vertical central section of a two-stage pump in which my invention is embodied;

Fig. 2 is a plan view of the lower half of the casing withthe impeller and shaft removed;

Fig. 3 is a sectional elevation shown in line.33 of Fig. 1;

Fig. l is a diagrammatic scheme of a passage connecting the two stages of the pump;

. Fig 5 is a plan view of a three-stage pump in whlch my invention is embodied; and

Fig. 6 is an end elevation thereof showing the pressure chamber in section; and V Fig. 7 is a sectlon on the line 77 of Fig. 6.

In certain particulars the constructionbof the present pump as shown in Figs. 1 to 3 resembles that disclosed in-"myPatent'No: 1,263,663 of April 23, 1918, in that it comprises two single suction impellers 10 and 11 arranged back to back with their single suetionsin opposite directions so as to balance the pump. The casing'is also divided on a horizontal plane into a lower section 12 and an upper section 13, bolted. together,

Specification of Letters Patent.

Patented Aug. 12, 1919.

Application filed April 24, 1919. Serial No. 292,363.

each carrying a portion of the partition 14 which separates the impeller chambers. The .lower section 12 carries the suction and discharge passages 15 and 16, respectively, with their connection ends. The driving shaft 9.

, is mounted between the two sections 12 and 13 with hearings in the partition 14 and in the casing Wall.

Instead of the tangential delivery passage of gradually increasing cross sectional area which connects the first and second stages of the pump shown in the patent above mentioned,'I now open the delivery volute 17 of the first stage directly downward into a large pressure chamber 18 formed in the foot of the pump. The volumetric capacity of the chamber is'so great that the velocity of the water is reduced far below the velocity in the suction head of the pump. Opening at right angles from this chamber and below the volute 19 ofthe second stage of the pump is a narrow passage 20 through which thewater passes with increased velocity. This passage de. velops into an upward lead 21 opening to the eye of the second iIrTpeller, and is of such varying cross sectional area that the velocity of the water is at first still further increased and then reduced again to that at the suction head of the first impeller. This has. the effect of straightening out the eddies formed in the stream of water during its passage through the narrow irregular open ing 20 beneath the second volute 19.

It will thus be seen that whereas in the since in pumps for this purpose the speed oQf the water is kept as low as possibleto minimize its corrosive action. By building the pressure chamber 18 of liberal proportions, the velocity of the water can be easily reduced, not only to an extent suflioient to prevent excessive corrosive action, but also to enable the current to make a sharp right angular turn without material iriction loss.

Furthermore, by forming the pressure chamber 18 in the foot of the pumpthe complicatedspiral passage of my Patent No. 1,263,663 is eliminated and the pattern and foundry work on the pump much simplifled, as well as doing away with the unnecessary Weight. This 'is an important point from the standpoint of economy, since a pump for handling acidulous waters must be built of acid resisting material such as bronze, the expense of which is high. Moreover, as it is customary to drive these pumps from an electric motor mounted on the same base plate as the pump, the motor standards are lower by reason of the lowered. position of the shaft, 9, and the weight of the installation' is thus further decreased. The volutes are set about 90 degrees apart to pro.

by coupling a unit of the present type Withanother unit of like type in which the suc- V tions are oppositely faced.

The pump casing com rises three sections, 25, 26 and 27, the rst two formin the pump body proper, while the section 2 comprises the pressure chamber connecting the several stages of the pump, the three sections being mounted upon a base plate 4 28. The suction pipe 29 is connected to the intake 30, opening to the eye of the impeller 31 in the volute. 22 of the first stage of the pump. Thi syolute discharges through a passage 32 to a pressure chamber 33 of great volumetric capacity and turns at right angles at relatively slow speed and high pressure downward to a passage 34 leading to the eye of the second stage impeller. The discharge fromthe second stage enters a second pressure chamber 35 separated from passage 34 bya partition 36, and is'in like manner led to the intake passage 37 for the third stage from which the water is dis charged through the pipe 38. I

through a pressure chamber of large capacity, in which the velocitv of the current is low, and from which the Water is discharged at a sharp angle to a passage leading the water at increased velocity to the succeeding stage of the pump.

shown in F igsh 5 to 7 the construction is such that the interiors of thepressure chambers may be lined with Wood or cement to protect the Walls of the chamber from the corrosive action of acidulous waters. Inasmuch as such a lining is readily formed,

due to the shape of the pressure chamber, it is possible to make this portion of the. pump casing of cast irona great economy in construction.

-Various modifications in detail will readily occur to those skilled in the art which do not depart from what lclaim as my invention. 7

I claim:

1. A multi-stage centrifugal pump having, between successivestages, a pressure chamber of large capacity towhich one stage delivers at relatively high velocity, and through which the fluid passes at relatively low velocity, a connecting passage leading therefrom at a sharp angle and of such reduced cross sectional area that the fluid is caused to pass therethrough at increased velocity to the succeeding stage of the pump. Y

2. A multi-stage centrifugal pump having, between successive stages, a pressure chamber of large capacity to which one stage delivers at relatively high velocity,

and through which the fluid passes at relatively low velocity, a connecting passage leading therefrom at a sharp angle and of suchreduced crdss sectional area that the I ing the fluid to the succeeding stage of the pump at substantially the same velocity as the suction of the preceding stage. i

3. A multi-stage centrifugal pump having, between successive stages, a pressure chamber of large capacity to which one stage delivers at relatively high velocity, and through which the fluid passes at relatively low velocity, a connecting passage leading therefrom at a sharp angle and of such reduced cross sectional area that the fluid is caused to pass therethrough at increased velocity to'the succeeding stage of the pump,

said connecting passage having a varying cross sectional'areato cause the fluid to pass from the pressure chamber at greatly increasedvelocity and then at reduced velocity at the point of delivery to the suction of the I I succeeding stage. In both constructions the Water passes from one stage to another of the pump 4. A multi-stage centrifugal pump havmg, between successive stages, a pressure chamber of large capacity to which one stage v ducedocross sectional area that the fluid In a pump of the three or more stage typeis caused to pass therethrough at increased velocity to the succeeding stage of the pump, said connecting passage having a varying cross sectional area to cause the fluid to pass from the pressure chamber at increased velocity, then at further accelerated velocity and finally at reduced velocity at the point of delivery to thesuction ofthe succeeding stage.

5. A multi-s-tage centrifugal pump having, between successive stages, a pressure chamber of large capacity to which one stage delivers at relatively high velocity,

and through which the fluid passes at rela tively low velocity, a connecting passage leading therefrom at a sharp angle and of such reduced cross sectional area that the fluid is caused to pass therethrough at increased velocity to the succeeding stage of the pump, said connecting passage having a varying cross sectional area to cause the fluid to pass from'the pressure chamber at increased velocity, then at further accelerated velocity, and finally at reduced velocity at the point of delivery to the suction of the succeeding stage, the velocity at the point of delivery to the succeeding stage corresponding substantially to the suction velocity of the preceding stage.

6. A centrifugal pump having two single suction impellers arranged back to back with their single suctions in opposite directions and with volute deliveries, a pressure chamber of large capacity to which the first volute discharges, a passage of relatively small cross sectional area opening at a sharp angle to said pressure chamber and leading the fluid at increased velocity to the eye of the second impeller.

7. A centrifugal pump having two single suction impellers arranged back! to back withtheir single suctions in opposite directions and with volute deliveries, a pressure angle to said pressure chamber to the eye of the second impeller,

foot of the pump casing, to which the first volute discharges, a passage of relatively small cross sectional area opening at a sharp and leading the fiuid at increased'velocity to the eye of the second impeller.

9. A centrifugal pump-having two single suction impellers arranged back to back with their single suctions in opposite direce tions and with volute deliveries, a pressure chamber of large capacity to which the first volute discharges, a passage of varying cross sectional area opening at a sharp angle to the pressure chamber and leading therefrom the shape of such passage being suchvas to cause the fluid to pass from the pressurechanrber at increased velocity, which is reduced at the point of delivery. to the second impeller to a velocity substantially corresponding to' the suction velocity of the first impeller.

In testimony whereof I have signed my name to this specification. i.

OTTO HAENTJENS. 

